Hot-dip galvanized steel
The hot-dip galvanized steel S250GD in accordance with EN 10346 combines a medium strength class with first-class corrosion protection and ease of processing. Thanks to the minimum yield strength of 250 N/mm² and the wide range of coating options, S250GD can be used flexibly in numerous construction applications – from roofs and façades to load-bearing lightweight structures. Construction companies and planners benefit from its long service life, excellent formability and individual adaptability to specific environmental requirements. S250GD is therefore an economical and sustainable solution for modern construction projects.
S250GD galvanized steel sheet is engineered for structural performance while offering flexible surface options that enhance corrosion resistance and appearance. While yield strength and formability are important, the surface treatment of S250GD is often the decisive factor in product selection, especially for exposed or painted applications.
-
Hot-Dip Galvanizing Process Explained
The continuous hot-dip galvanizing process coats S250GD steel evenly on both sides. This process ensures:
Uniform zinc distribution
Strong adhesion between zinc and steel
Long-term corrosion protection
The resulting surface can be customized through spangle control and post-treatment.
-
Zinc Coating Weight Selection Guide
Table 1 – Coating Weight vs. Service Life
| Coating Type | Zinc Mass (g/m²) | Expected Durability* |
|---|---|---|
| Z100 | 100 | Short-term indoor |
| Z140 | 140 | Standard outdoor |
| Z180 | 180 | Long-term outdoor |
| Z220 | 220 | Severe environments |
*Durability depends on climate and exposure conditions.
- Zinc Thickness
| Zinc Coating Grade | Zinc Coating (g/m²) | Corrosion Resistance | Typical Applications | Remarks |
| Z30 | 30 | Very low | Indoor parts, home appliance inner panels, ventilation ducts | Not suitable for outdoor use |
| Z60 | 60 |
Low |
Indoor structures, temporary facilities | Low cost |
| Z80 | 80 | Medium | Light steel structures, base metal for PPGI | Good cost performance |
| Z100 | 100 | Medium | PPGI, fencing, general construction
|
Common export grade |
| Z120 | 120 | Medium-High |
|
Longer service life |
| Z140 | 140 | Medium-High | Industrial buildings, agricultural facilities | Suitable for outdoor use |
| Z180 | 180 | High | Long-term outdoor structures, equipment housings
|
Recommended for outdoor use |
| Z200 | 200 | Very high | Humid environments, heavy structures
|
Higher cost |
| Z275 | 275 | Excellent
|
Coastal areas, solar mounting systems, high-corrosion environments | High standard |
-
Zinc Spangle Selection and Its Impact
Regular Spangle
Provides a classic galvanized appearance. Suitable for applications where appearance is secondary to performance.
Minimized Spangle
Enhances uniformity and reduces visual contrast, making it ideal for visible structures.
Zero Spangle
Chosen for premium painted surfaces where consistency is critical.
Table 2 – Spangle Options and Performance
| Feature | RS | MS | ZS |
|---|---|---|---|
| Visual Quality | Standard | High | Premium |
| Paint Adhesion | Good | Very Good | Excellent |
| Cost Level | Economical | Moderate | Higher |
-
Advanced Surface Treatments
Passivation: Prevents white rust during transport.
Anti-Fingerprint: Improves handling quality.
Paint-Ready Finish: Enhances coating adhesion.
Typical Dimensions with Surface Options
Table 3 – Supply Range
| Thickness (mm) | Width (mm) | Available Surfaces |
|---|---|---|
| 0.50 | 800–1250 | RS / MS |
| 0.75 | 900–1500 | MS / AFP |
| 1.20 | 1000–1500 | MS / AFP / ZS |
Selecting the right S250GD surface treatment ensures optimal performance, appearance, and lifecycle cost.
GNEE STEEL provides professional guidance, stable quality, and customized surface solutions.
📩 Reach out to GNEE STEEL today to discuss coating and spangle options for your project.
